Simulated limb joint construction



Sept. 4, 1956 J. WEIH SIMULATED LIMB JOINT CONSTRUCTION Filed NOV. 1,1954 2 Sheets-Sheet 1 FIG. 3;

FIG. I.v

INVENTOR JULIUS WEIH.

ATTORNEYS.

Sept. 4, 1956 J. WEIH 2,761,245

SIMULATED LIMB JOINT CONSTRUCTION Filed Nov. 1, 1954 2 Sheets-Sheet 2INVENTOR JULIUS WEIH.

Ww r M ATTORNEYS.

United States Patent SIMULATED LIMB JOINT CONSTRUCTION Julius Weill,Ozone Park, N. Y., assignor to Ideal Toy gorpioration, New York, N. Y.,a corporation of New Application November 1, 1954, Serial No. 465,923

8 Claims. (Cl. 46-173) This invention relates generally to simulatedlimb con- 'structions, and is particularly concerned with accuratelysimulated human or animal limbs having articulated members of thegeneral type disclosed in my prior copending patent applications Ser.Nos. 428,920 filed May 24, 1954, and 437,354 filed June 17, 1954, theinstant invention being an improvement over such disclosures.

The particular embodiment of the present invention, which is illustratedin the drawings and which will be described hereinafter in greaterdetail, comprises generally a pair of simulated limb members, andconnecting means serving to hold the limb members together and permitlife-like, relative swinging movement of the limb members.

It is a general object of the present invention to provide a simulatedlimb construction of the type described in which the members are movablerelative to each other to afford the realistic appearance of :a human oranimal limb, and which may be utilized in dolls, puppets, artificialanimals and various other devices to accurately simulate walking andother normal limb movements.

It is another object of the present invention to provide a simulatedlimb construction having the advantageous characteristics mentioned inthe foregoing paragraph, which may be simply and easily manipulated,even by a small child, to present the life-like :appearance of a widevariety of limb positions. In addition, the limb construction of thepresent invention is adapted to be selfretaining in substantially anydesired position into which it may be manipulated, while being readilyreleasable for further manipulation into dilferent positions.

It is a more particular object of the present invention to provide asimulated limb construction of the type described, in which the limbmember connecting means serves both to hold the members together andmaintain the members in a wide variety of angular dispositions. Further,the novel limb construction of the present invention permits ofactuation (relative movement of the limb members) by a small andsubstantially constant force, over practically the entire range ofrelative angular dispositions. That is, there are no dead positionsthrough which it is relatively difficult to effect swinging movement ofthe limb members.

It is a further object of the present invention to provide a simulatedlimb construction having the advantageous features mentioned above,which is simple and durable in construction, wherein normal wear of thelimb members is automatically compensated for or taken up to afford longcontinued, trouble-free operation, and which can be manufactured andsold at a reasonable cost.

Other objects of the present invention will become apparent upon readingthe following specification and by referring to the accompanyingdrawings, which form a material part of this disclosure.

The invention accordingly consists in the features of construction,combinations of elements, and arrangements of parts, which will beexemplified in the construction hereinafter described, and of which thescope will be indicated by the appended claims.

In the drawings:

Figure 1 is a side elevational view, partly broken away, showing asimulated leg constructed in accordance with the present invention, thelower leg member being illustrated in its substantially aligned relationwith respect to the upper leg member or thigh;

Fig. 2 is a sectional view taken substantially along the line 2-2 ofFig. 1;

Fig. 3 is a partial, elevational view showing the external appearance ofthe joint connecting the upper and lower leg members;

Fig. 4 is a partial, vertical sectional view similar to Fig. 1, andshowing the lower leg member in an intermediate rearwardly angulatedposition with respect to the upper leg member;

Fig. 5 is a partial, sectional view similar to Fig. 4 showing therearward leg member in its fully angulated position with respect to theupper leg member;

Fig. 6 is :a partial, rear elevational view of the lower portion of theupper leg member, with parts broken away for purposes of illustration;and

Fig. 7 is a top plan view of the upper end of the lower leg member.

While the limb construction of the present invention is equally welladapted for simulating a wide variety of limbs, both human andotherwise, the invention has been primarily developed and employed inconnection with doll legs, and will be described hereinafter withparticular reference thereto.

Referring now more particularly to the drawings, the embodiment of theinvention illustrated therein comprises a simulated thigh or upper legmember, generally designated 10, and a simulated lower leg member,generally designated 11, which is articulated to the thigh member by thejoint 12.

The thigh member 10 is preferably hollow and of generally ovaloidcross-section. The front or forward wall portion 15 of the thigh member10 is provided with an internal boss 16 adjacent to and spaced above thelower end of the thigh; and an oppositely disposed, internal boss 17 isformed on the back or rearward thigh wall portion 18. Extending betweenthe internal bosses 16 and 17, and having its opposite ends securedtherein, is a rod 19, which is formed with a downwardly bent or loopedportion 20 adjacent to and spaced from the forward wall portion 15.

The inner limb-member or thigh member 10 has a lower or forward end 23.A socket, generally designated by the reference numeral 21, is providedat the joint 12. A bulb-shaped bearing 38 is provided in leg member 11at joint 12.

As viewed in Fig. l, the rear wall-portion of thigh member 10 terminatesin a bottom end-wall 25; socket 21 has a front wall portion or extension24 which has an external rib 14 and an internal bearing face 22 and abottom end 28; bearing 38 has a front wall portion 40 which interfitswith bearing face 22; bearing 38 has a rear wall portion 41 which has anupper end-wall 29 which interfits with end-wall 25 of thigh member 10;and there is an angular junction 44 at the bottom of rear wall portion41.

In Fig. l, the reference numerals 41 and 40 designate arcs of respectivecircles of different respective radii, having a common center. Thiscommon center is on a pivotal axis of relative turning movement betweenthigh member 10 and leg member 11. Said pivotal axis is a transverseaxis of the joint 12. Said pivotal axis is perpendicular to the plane ofFig. 1. As seen in Fig. 5, the relative turning movement between thighmember 10 and leg member 11 is not more than When the leg member 11 isturned clockwise, as viewed in Fig. 1, from its normal longitudinallyalined position of Fig. l, the bearing 38 is guided at the bearing face22 and at the end-wall 25 of thigh member 10.

At its rear, the bearing 38 has hooked stop lugs 43. When the leg member11 is in its normal longitudinally alined position of Fig. 1, said stoplugs 43 abut and engage the rear portion of thigh member 10, so that, asviewed in Fig. 1, the outer leg member 11 cannot be turnedcounterclockwise or reversely relative to thigh or inner member 10, whenleg member 11 is in its normal position of Fig. 1.

The lower leg member 11 is also preferably hollow, including front andrear wall portions and 31, respectively, and a lower end foot simulatingportion 32. Interiorly of the lower leg member 30 on the forward andrearward wall portions, respectively, are formed opposed bosses 33 and34 which support opposite ends of a rod 35. The rod 35 is preferablyinclined forwardly for a purpose appearing presently.

The socket 21 is adapted to conformably receive the bulb 38, the latterbeing rotatably engaged within the socket. As both the socket and bulbare substantially ovaloid in horizontal section, relative rotation willbe constrained about a single transverse, substantially horizontal axis.

Depending from the rod 19, through the thigh opening 23 and the bulbcutout 39, into the bulb 38 is a link or connecting member, generallydesignated 45. The link is preferably formed of stiff wire and has itsupper end hooked, as at 46, and engaged over the looped rod portion 20to define a pivotal connection between the rod 19 and link. The lowerportion of the wire link 45 is coiled to form a rearwardly enlarged loopor abutment 47, which is disposed within the bearing 38.

A resiliently extensile and contractile tension member, generallydesignated 49 is disposed interiorly of the lower leg member 11, and maycomprise a helical coil spring, as shown in the drawings, an elasticband, or other suitable tensioning device, as desired. The lower end ofthe tension member 49 is coiled about the rod 35, as at 50, and theupper end of the tension member is coiled about a portion of the loop 47as at 51. As the spring 49 is held under tension, its lower end 50 willbe drawn forwards along the forwardly inclined rod 35 and maintained ina position adjacent to the boss 33. Thus, it will now be understood thatthe link 45 and tension member 49 serve to hold the bulb 38 inengagement within the socket 21, while the loop 20 in the bar 19 and theinclined disposition of the bar 35 serve to p0- sition the link andtension member relative to the axis of swinging movement of the upperand lower leg members 10 and 11.

As seen in Fig. 1, the loop 47, connecting the link 45 and tensionmember 49, is disposed forwardly of the axis of limb member rotation, soas to yieldably maintain the limb members in the illustrated straight oraligned position. However, upon slight rearward angular movement orswinging of the lower limb member 11 relative to the upper limb member10, to the position illustrated in Fig. .4, the connecting loop 47shifts rearwardly into abutting engagement with the rearward bulbportion 41. In this position, the connecting loop 47 of the link 45 isdisposed generally in alignment with or in close proximity to thetransverse axis of relative limb member movement, so that the forceexerted by the spring 49 will be in substantial alignment with the lastnamed axis. Hence, there will be little or no component of the springforce tending to cause rotation of the lower limb member relative to thethigh member, and swinging movement of the lower limb member maytherefore be effected by merely overcoming the frictional resistance inthe joint 12. The condition in which the connecting loop 47 is disposedin close proximity to the axis of limb member rotation is approximatedthroughout the rearward angulation of the lower limb member 11 to theextreme position of Fig. 5. Of course, forward swinging movement of thelower limb member effects mere reversal of the above describedoperation, wherein the connected ends of the link 45 and tension member49 are disposed in close proximity to the axis of limb member rotationthroughout a substantial portion of the latter rotation, tosubstantially eliminate or efiectively reduce all spring forcecomponents tending to effect relative swinging movement of the limbmembers. As the lower limb member 11 approaches its forwardmost, alignedposition of Fig. 1, the connected ends of the tension member 49 and link45 will shift forwardly of the limb member axis and effect a slightkicking of the lower limb member into its aligned position.

it will now be apparent that the above described doll limb constructionaffords a substantially constant re sistance to swinging movement of thelimb members throughout a substantial portion of its swinging movement.Further, such resistance is determined by the tension or strength of thetension member 49 and the snugness of fit between the socket 21 and bulb35, which are preferably predetermined so that the lower limb memberwill be self-retaining in any selected position of its angulardisposition with respect to the upper limb member over that portion ofthe lower limb swinging movement in which the connecting loop 47 is inthe immediate region of the limb rotation axis. Of course, the springmust be of sufiicient strength to resiliently hold the upper and lowerlimb members together, so as to take up any looseness therebetween andthus compensate for wear.

While the leg members have been illustrated in the drawings as formed ofplastic material, which is preferred for its molding characteristics andsurface qualities, it is appreciated that other suitable materials maybe employed without departing from the spirit and scope of the presentinvention.

As viewed in Fig. l, the tension spring 49 is located to exert acounterclockwise torque upon leg 11, but the longitudinalcounterclockwise turning movement of leg 11 is prevented by thehook-stops 43. As shown in Fig. l, the inner convex wall 22, which islongitudinally concentric with the pivotal axis of the joint, extendsbelow said pivotal axis when the leg 11 is in its normal selectedposition of Fig. 1. The hook-stops 43 and the engagement of walls 22 and40 below the pivotal axis, make it impossible to pull the leg out of thejoint. The counterclockwise torque of spring 49 yieldingly maintains theleg 11 in its normal selected position of Fig. 1.

Fig. 4 shows an intermediate inclined position of leg 11. Due to theforward and upward inclination of rod 35, the lower spring-look 50remains at the front wall of the leg 11.

In Fig. 4, the link 45 has been turned clockwise rela tive to thigh 10,from the position of link 45 in Fig. l. in both Fig. 1 and Fig. 4, thereis a straight line between the upper turnable end of link 45 and thelower springloop 50. In Fig. 4, it is clear that the tension of spring49 exerts a clockwise torque on leg 11, which urges leg 11 to the fullyinclined or kneeling position of Fig. 5.

When leg 11 is turned clockwise beyond its intermediate position of Fig.4, the rear bearing-head wall 41 turns link 45 counterclockwise from itsintermediate position of Fig. 4. Hence when the leg 11 is in its fullyinclined position of Fig.5, the spring 49 exerts little or no torque.

For convenience, the limb is defined in the claims with reference to theviews of Figs. 1, 4, 5 and the inner limb member is defined as the thighand the outer limb memher is defined as the leg. However, it is clearthat the invention is not limited to a lower limb.

From the foregoing, it is seen that the present invention provides asimulated limb construction which fully accomplishes its intendedobjects, and which is well adapted to meet practical conditions ofmanufacture and use.

Although the invention has been described in some detail by way ofillustrating an example for purposes of clarity of understanding, it isunderstood that certain changes and modifications may be made within thespirit of the invention and scope of the appended claims.

What is claimed is:

1. A simulated limb which has a thigh member and a leg member which havea joint at their adjacent ends; said leg member being longitudinallyturnable in said joint relative to said thigh about a pivot joint axiswhich is transverse relative to said thigh and leg; said leg being thusturnable counterclockwise about said pivot axis to a normal selectedposition and being thus turnable clockwise about said pivot axis out ofsaid normal selected position, said thigh having a front thigh-wall anda rear thigh-wall; said leg having a front leg-wall and a rear leg-wall;said front thigh-wall having a front socketextension in said joint whichextends below the lower end of said rear thigh-wall; saidsocket-extension having an inner concave bearing face which islongitudinally concentric with said pivot axis in said turningdirections; said leg having a bearing-head in said joint; saidbearinghead having a front convex bearing-head wall which turnablyinterfits with said concave bearing face; said bearing-head having arear bearing-head wall having an upper end portion, a hook stop carriedby said upper end portion and having a rearwardly projecting hookportion, said lower end of the rear thigh-wall having an inwardlyprojecting abutment against which the hook portion strikes to arrest thecounterclockwise movement of the leg and position the leg in a normalposition, said hook stop being moved out of engagement with saidabutment on the rear wall of the thigh when said leg is turned clockwiseout of said selected normal position; said concave bearing face having aportion extending below said pivot axis and interfitting with thatportion of said front convex wall which extends below said pivot axiswhen said leg is in said normal positon.

2. A smulated limb which has a thigh member and a leg member which havea joint at their adjacent ends; said leg member being longitudinallyturnable in said joint relative to said thigh about a pivot joint axiswhich is transverse relative to said thigh and leg; said leg being thusturnable counterclockwise about said pivot axis to a normal selectedposition and being thus turnable clockwise about said pivot axis out ofsaid normal selected position, said thigh having a front thigh-wall anda rear thigh-wall; said leg having a front leg-wall and a rear leg-wall;said front thigh-wall having a front socketextension in said joint whichextends below the lower end of said rear thigh-wall; saidsocket-extension having an inner concave bearing face which islongitudinally concentric with said pivot axis in said turningdirections; said leg having a bearing-head in said joint; saidbearinghead having a front convex bearing-head wall which turnablyinterfits with said concave bearing face; said bearing-head having arear bearing-head wall which has a hook-stop; said hook-stop beinglocated to engage said thigh when said leg is in said normal position;said hook stop being moved out of engagement with said thigh when saidleg is turned clockwise out of said selected normal position; saidconcave bearing face having a portion extending below said pivot axisand interfitting with that portion of said front convex wall whichextends below said pivot axis when said leg is in said normal position,said concave bearing face and said front bearing-head wall havingnon-circular lateral cross-sections to prevent said leg from turningsideways or twisting relative to said thigh.

3. A simulated limb which has a thigh member and a leg member which havea joint at their adjacent ends; said leg member being longitudinallyturnable in said joint relative to said thigh about a pivot joint axiswhich is transverse relative to said thigh and leg; said leg being thusturnable countenclockwise about said pivot axis to a normal selectedposition and being thus turnable clockwise about said pivot axis out ofsaid normal selected position, said thigh having a front thigh-wall anda rear thigh-wall; said leg having a front leg-Wall and a rear leg-wall;said front thigh-wall having a front socket-ex tension in said jointwhich extends below the lower end of said rear thigh-wall; saidsocket-extension having an inner concave bearing face which islongitudinally concentric with said pivot axis in said turningdirections; said leg having a bearing-head in said joint; saidbearing-head having a front convex bearing-head wall which turnablyinterfits with said concave bearing face; said bearing-head having arear bearing-head wall which has a hook-stop; said hook-stop beinglocated to engage said thigh when said leg is in said normal position;said hook stop being moved out of engagement with said thigh when saidleg is turned clockwise out of said selected normal position; saidconcave bearing face having a portion extending below said pivot axisand interfitting with that portion of said front convex wall whichextends below said pivot axis when said leg is in said normal position,said rear bearing-head wall being also convex and being alsolongitudinally concentric with said pivot axis, said ho0k-st0p beingfixed to the upper end of said rear bearing-head wall and engaging thelower end of said rear thigh-wall when said leg is in said normalselected position.

4. A simulated limb which has a thigh member and a leg member which havea joint at their adjacent ends; said leg member being longitudinallyturnable in said joint relative to said thigh about a pivot joint axiswhich is transverse relative to said thigh and leg; said leg being thusturnable counterclockwise about said pivot axis to a normal selectedposition and being thus turnable clockwise about said pivot axis out ofsaid normal selected position, said thigh having a front thigh-wall anda rear thighwall; said leg having a front leg wall and a rear leg-wall;said front thigh-wall having a front socketextension in said joint whichextends below the lower end of said rear thigh-wall; saidsocket-extension having an inner concave bearing face which islongitudinally concentric with said pivot axis in said turningdirections; said leg having a bearing-head in said joint; saidbearinghead having a front convex bearing-head wall which turnablyintcrfits with said concave bearing face; said bearing-head having arear bearing-head wall which has a hook-stop; said hook-stop beinglocated to engage said thigh when said leg is in said normal position;said hook stop being moved out of engagement with said thigh when saidleg is turned clockwise out of said selected normal position; saidconcave bearing face having a portion extending below said pivot axisand interfitting with that portion of said front convex wall whichextends below said pivot axis when said leg is in said normal position,said rear bearing-head wall being also convex and being alsolongitudinally concentric with said pivot axis, said hook-stop beingfixed to the upper end of said rear bearing-head wall and engaging thelower end of said rear thigh-wall when said leg is in said normalselected position, the longitudinal curvature of said rear convexbearing-head wall being greater than the longitudinal curvature of saidfront convex. bearing-head wall.

5. A simulated limb which has a thigh member and a leg member which havea joint at their adjacent ends; said leg member being longitudinallyturnable in said joint relative to said thigh about a pivot joint axiswhich is transverse relative to said thigh and leg; said leg being thusturnable counterclockwise about said pivot axis to a normal selectedposition and being thus turna'ble clockwise about said pivot axis out ofsaid normal selected position, said thigh having a front thigh-wall anda rear thigh-wall; said leg having a front leg-wall and a rear leg-wall;said front thigh-wall having a front socketextension in said joint whichextends below the lower end of said rear thigh-wall; saidsocket-extension having an inner concave bearing face which islongitudinally concentric with said pivot axis in said turningdirections; said leg having a bearing-head in said joint; saidbearinghead having a front convex bearing-head wall which turnablyinterfits with said concave bearing face; said bearing-head having arear bearing-head wall which has a hook-stop; said hook-stop beinglocated to engage said thigh when said leg is in said normal position;said hook stop being moved out of engagement with said thigh when saidleg is turned clockwise out of said selected normal position; saidconcave beaming face having a portion extending below said pivot axisand interfitting with that portion of said front convex wall whichextends below said pivot axis when said leg is in said normal position,and a tension spring located in said limb and shiftably connected tosaid thigh and leg, said tension spring being located to exert acounterclockwise torque on said leg when said leg is in said normalselected position, said spring being shifted and located to exert aclockwise torque when said leg is turned clockwise to an intermediateangular position, said leg being turnable clockwise beyond saidintermediate angular position.

6. A simulated limb which has a thigh member and a leg member which havea joint at their adjacent ends; said leg member being longitudinallyturnable in said joint relative to said thigh about a pivot joint axiswhich is transverse relative to said thigh and legs; said leg being thusturnable counterclockwise about said pivot axis to a normal selectedposition and being thus turnable clockwise about said pivot axis out ofsaid normal selected position, said thigh having a front thigh-wall anda rear thigh-wall; said leg having a front leg-wall and a rear leg-wall;said front thigh-wall having a front socket-extension in said jointwhich extends below the lower end of said rear thigh-wall; saidsocket-extension having an inner concave bearing face which islongitudinally concentric with said pivot axis in said turningdirections; said leg having a bearing-head in said joint; saidbearing-head having a front convex bearing-head wall which turnablyinterfits with said concave bearing face; said bearing-head having arear bearing-head wall which has a hook-stop; said hook-stop beinglocated to engage said thigh when said leg is in said normal position;said hook stop being moved out of engagement with said thigh when saidleg is turned clockwise out of said selected normal position; saidconcave bearing face having a portion extending below said pivot axisand interfitting with that portion of said front convex wall whichextends below said pivot axis when said leg is in said normal position,a link which is located in said thigh and in said joint, the upper endof said link being turnably connected to said thigh to turn around anupper transverse axis which is located above said pivot axis, said linkhaving a link-loop in said joint, a tension spring, the upper end ofsaid tension spring having a spring-loop which slidably engages saidlink-loop, the lower end of said spring being connected to said leg atits front leg-wall, said spring being located to exert acounterclockwise torque on said leg when said leg is in said normalselected position, said link being located to be engaged by said rearbearing-head wall when said leg is turned clockwise to an intermediateinclined position beyond which said leg is clockwise turnable, saidrear-bearing head wall engaging said link to turn said linkcounterclockwise around its upper transverse axis when said leg isturned clockwise beyond said intermediate position.

7. A simulated limb which has a hollow thigh member and a hollow legmember which have a joint at their adjacent ends; said leg beinglongitudinally turnable in said joint relative to said thigh about apivot joint axis which is transverse relative to said members; saidthigh having an inner lateral thigh-rod fixed thereto above said joint;said leg having an inner lateral leg-rod fixed thereto below said joint,said thigh having a front thighwall and a rear thigh-wall, said leghaving a front legwall and a rear leg-wall, said leg-rod being upwardlyand forwardly inclined, said front thigh-wall having a frontsocket-extension in said joint which extends below the lower end of saidrear thigh-wall, said socket extension having an inner concave bearingface which is longitudinally concentric with said pivot joint axis andwhich has a non-circular lateral cross-section; said leg having abearing-head in said joint, said bearing-head having a front convexbearing-head wall which interfits with said concave bearing face, saidbearing-head having a rear convex bearing-head wall of greaterlongitudinal curvature than said front-bearing head; a link which has anupper end which is pivotally connected to said thigh-rod to turn about alink axis which is parallel to said pivot joint axis, said link having alink-loop in said joint at the lower end of said link, a tension spring,said tension spring having an upper spring-loop which slidably engagessaid link-loop, said tension spring having a lower springloop whichslidably engages said leg-rod, said rear bearing head-wall having ahook-stop at its upper end, said leg being turnable counterclockwiseabout said pivot joint axis to a normal position in which said hook-stopengages the bottom end of said rear thigh-wall to prevent furthercounterclockwise turning movement of said leg, said spring being locatedto exert a counterclockwise torque on said leg when said leg is in saidnormal position, said leg being turnable about said pivot joint axis ina clockwise direction to an intermediate inclined position and to afinal inclined position, said link being turned clockwise around saidlink axis when said leg is turned to said intermediate position, saidspring being located to exert a clockwise torque on said leg when saidleg is in said intermediate position, said rear bearing-head wall beinglocated to abut said link and to turn said link counterclockwise aroundits link-axis when said leg is turned clockwise from said intermediateinclined position to said final inclined position, said spring beingsubstantially alined with said pivot joint axis when said leg is in saidfinal inclined position.

8. A simulated hollow limb which has a longitudinal axis, said simulatedlimb having a hollow upper limbmember and a hollow lower limb memberwhich are turnable relative to each other in a common joint around apivot axis which is transverse relative to said longitudinal axis, saidupper limb member having a front wall and a rear wall, said rear wall ofsaid upper member having a bottom edge in said joint, said front wall ofsaid upper member having a concavo-convex extension which extends belowsaid bottom edge of said rear wall of said upper member, saidconcave-convex extension having a concave inner face, said lower memberhaving a front convex wall which interfits in said joint turnably withthe concave inner face of said concave-convex extension when said lowermember is aligned with said upper member and also when said lower memberis substantially perpendicular to said upper member, said lower memberhaving a rear wall in said joint, said rear wall of said lower memberbeing convex and having a rearwardly projecting abutment means providedadjacent its upper edge, said rear wall of the upper member having aninwardly extending projection on its bottom edge against which theabutment means is adapted to strike to arrest the counterclockwisemovement of the lower member and position the lower member in normalposition of alignment with the upper member, said rear wall of the lowermember having a shoulder junction with the adjacent part of said lowermember at the lower edge of said convex rear wall of said lower member,said shoulder junction being located to contact with said bottom edge ofsaid rear wall of said upper member when said lower member is turnedbackward in said joint relative to said 1,654,933 upper member.2,350,114 2,498,141 References Cited in the file of this patent UNITEDSTATES PATENTS 5 11 489 982,096 Sehoenhut Jan. 17, 1911 134:7751,315,820 De Saunier Sept. 9, 1919 49 723 1,423,382 Zaiden July 18, 192210 v Heyman Jan. 3, 1928 Katz May 30, 1944 Stokes Feb. 21, 1950 FOREIGNPATENTS .Great Britain 1897 France Jan. 27, 1880 Great Britain Jan. 31,1951

